Some time ago I was watching a lady on TV (guest on some quilting show) and she had one foot on the front of the 'pedal' and the other on the back. She said she had better control that way and even stitches.
As I haven't used a treadle in almost a thousand years I can't verify this information. I do know that when I was a teen a friend had a treadle and she made all her own clothes with the thing and did beautiful work.
Good luck and enjoy your new baby.